A conventional portable telephone set is constructed to contain a transmission and receipt unit for transmitting a speech signal of a user (caller or callee) via a rod antenna and receiving a transmitted signal from the rod antenna, and a speaker unit for converting the received electric signal to a sound signal to be heard by the user in a housing case, wherein the housing case is provided with a speaker portion in the inside of which the speaker unit is positioned, and a microphone portion in the inside of which a microphone unit for converting a sound signal of the user to an electric signal to be supplied to the transmission and receipt unit is positioned, while the rod antenna is contained in the housing case to be pulled out in a direction parallel to a side plane of the housing case in operation and pushed thereinto in the idle state.
In operation, the rod antenna is pulled out from the housing case, and a switch is turned on, respectively, by the user, so that the transmission and receipt of telephone signals are carried via the rod antenna. In this operation state, the housing case is held vertically by the user, such that the speaker portion is in contact with an ear of the user, and the microphone portion is in the vicinity of a mouth of the user. Consequently, the rod antenna extends vertically to be partially positioned on the side of a head of the user.
In the conventional portable telephone set, however, there is a disadvantage in that electric signals transmitted from and received by the rod antenna are absorbed by the head of the user, thereby resulting in the decrease of a gain for the rod antenna. As a result, a communication area of the portable telephone set becomes narrow. Further, there is possibility in which a line connection is turned off instantly, when the speaker portion becomes contact with the ear of the user, even if the telephone set is turned on by receiving a call signal.